The present invention generally relates to catheters. More specifically, the present invention relates to intravascular microcatheters.
Intravascular catheters are used to diagnose and treat a wide variety of vascular diseases in various parts of the human vasculature. To access the cerebral vasculature, as well as other remote and tortuous vascular sites, it is desirable to have a catheter that has good navigational capabilities.
To address this need, the present invention provides, in one example, an intravascular microcatheter having a relatively stiff proximal shaft (e.g., super elastic hypotube) for pushability and torqueability. The microcatheter also includes a relatively flexible distal shaft portion (e.g., coil reinforced multi-layered gradient polymer tube) for trackability. To provide a smooth transition between the relatively stiff proximal shaft and the relatively flexible distal shaft, a transition region is provided by integrating portions of the proximal shaft and portions of the distal shaft in a manner that provides a secure connection and that minimizes profile increase. The result is a low profile microcatheter having superior response and control to navigate through tortuous vasculature to remote vascular sites.